Boiler



March 5, 1935. T. E. MURRAY BOILER Filed Oct. 9, 1925 5-Sheets-Sheet 1T. E. MURRAY March 5, 193 5.

BOILER Filed Oct. 9', 1925 5 Sheets-Sheet 2 March 5, 1935.

T. E. MURRAY BOILER Filed Oct. 9, 1925 5. Sheets-Sheet s vwento'c March5, 1935. T. E. MURRAY 1,993,072

BOILER Filed 001;. 9, 1925 5 Sheets-Sheet 4' avwwntoz Zia/mas E MURRA KMarch 5, 1935. T. E. MURRAY 1,993,072

BOILER Filed Oct. 5, 1925 5 Sheets$heet 5 Patented Mar. 5, 1935 PATENTQFFICE,

BOILER Thomas E. Murray, Brooklyn, N. Y.; Joseph Bradley Murray, ThomasE. Murray, Jr., and John F. Murray, executors of said Thomas E. Murray,deceased, assignors to Metropolitan Engineering Company, a corporationof New York .Rnssuro DEC 3 1940 Application October 9, 1925, SerialNo.'61,386

6 Claims.

In certain previous applications, particularly No. 642,725, patentedFeb. 11, 1930, Patent No.

1,746,711, I have described boilers having walls 01" banks of watertubes exposed to the direct radiant heat of the burning fuel, wherebythe rating or production of steam is very much increased as comparedwith boilers of previous types.

The present invention is directed to a boiler in which this principle isutilized to the fullest possible extent, and is directed to variousother features described in detail hereinafter. The

. accompanying drawings illustrate embodiments Fig. 5 is a horizontalsection of the lower part of one of the boiler walls.

I Figs. 6 and 7 are partial horizontal sections il- I lustratingmodifications.

Figs. 8, 9 and 10 are vertical sections illustrating 'difierent uses ofthe hot gases passing out of the combust-ion'chamber.

Referring first to Fig. l'there are front walls 1, back walls 2 and sidewalls 3 composed of vertical tubes spaced apart with flanges extendingacross the spaces, and similar longitudinal tubes arranged to form a topwall 4 and bottom wall 5. The firing nozzles or grate and the passagesfor the gases are omitted from this figure, as are also the surroundingwalls of refractory material. These details may be varied in design andarrangement, as illustrated for example inthe other figures.

The tubes of the front and rear walls 1 and 2 andof the bottom wall 5communicate at their lower ends with headers 6 and 7. The tubes of theopposite side walls 3 communicate with bot-- tom headers 8 which areconnected at their ends to the ends of the headers 6 and 7. A header 9on the upper ends of the tubes 2 communicates with the tubes 4 of thetop wall and also with the endsof the upper headers 10 of the side,

walls. A steam drum 11 receives steam directly from the tubes of thefront wall -1 and of the top wall 4 and also from the upper headers 10.The steam is taken off from the drum in any way. The water from the drumpasses out of its ends by down-comers 12 to the lower headers 8. Thetubes and headers which are shown horizontal may be slightly inclinedupward in the direction of flow if preferred, and the circulation may beprovided for in various other ways.

The water entering the lower headers 8 passes into the headers 6, thebottom wall 5 and the lower ends of the front, back and side wall tubes.Thence the wet steam and water pass upward to the headers 9 and 10, thetop wall 4 and the upper'end of the front wall 1, where they pass intothe drum 11.-

The fuel is burned in the combustion chamber enclosed by the tubularwalls, so that all the tubes are exposed to the direct radiant heat ofthe burning fuel and steam is generated at'a very high rate and veryefliciently. F

As illustrated in Fig. 2, the individual tubes 13 are provided each withtwo flanges 14 overlapping those of the adjacent tubes, so as tosubstantially close the space between them, while leaving the tubes freeto expand or contract independently of one another, and to separatelyrenewed when necessary. A layer or wall of refractory or insulatingmaterial is arranged outside of the tubes. Preferably this consists ofplastic insulating material 15 tied to the tubes .by means of flanges 16on the latter having lateral extensions 17 embedded in the plasticmaterial. The flanges 14 and 16 are secured to the tubes by welding, orother methods.

Outside of the plastic material 15 there is (see Fig. 5) preferably afacing 18 of cement and a steel plate 19 fastened by means of anchors 20embedded in the insulating material and out of contact with the tubes toavoid conduction of heat therefrom. h

The vertical walls of the boiler made as describedare preferablysurrounded by a wall of brickwork or other masonry 21 built up againstan insulating plate 22 and a steel plate- 23bolted to columns 24 whichsupport the roof of the boiler or other parts of the surroundingstructure. The

space 25 between the outer and inner walls serves as an insulating airspace and may also be used as a preheating passage for the air used forcombustion.

In some boilers it is desirable to protect parts of the inner face ofthe water walls from too great heat or, for other reasons, to interposea shield between parts of the tubing and the combustion chamber. In suchcases the parts of the tubes to be shielded are provided 'withflanges'26, preferably having lateral extensions 27, and a layer ofplastic material 28 is applied, imbedding the flanges 26 and being thusreinforced and tied to the tubular structure.

In Fig. 4 the entire bottom wall is occupied by a stoker 29 on which thecoal is indicated at 30. The. line 31 indicates the top of therefractory protecting material 28. This part of the .side.

to those in Fig. but without flanges to tie in ""the refractorymaterial.

The materials which I have referred to herein as refractory are notnecessarily adapted to withstand extremely high'temperatures, as theterm is often understood in the art of furnace construction. They needbe only sufficiently refractory to withstand the temperatures to whichthey are severally exposed; which for some of these materials are notvery high.

Instead of using a grate fired boiler I prefer to use pulverized coal orsimilar jet fuel introduced through nozzles 36 (Fig. 2), arranged toinject the fuel in jets at different angles so as to secure a thoroughadmixture during combustion and a uniform distribution of the gasesagainst the different waterwalls. Preferably the burners or nozzles arearranged in sets of two or more 36 and 3'1 grouped together as in Fig. 3to provide for a wide variation in capacity of the boiler. When runningat the highest rating all the nozzles in a group will be used. For alower rating a smaller number of nozzles in each group may be used,securing the same velocity of the jets for a decreased quantity of fuel.

. Fig. 8 shows an arrangement of the nozzles at the lower end of thechamber and the exhaust gases from the boiler proper passing by anoutlet 38 to-and around tubes 39, a battle 40 and tubes 41 and thenceout by a flue 42. The tubes 39 and 41 may be any supplementary heatingdevices such as economizers, air heaters or superheaters, or evensupplementary boiler tubes.

According to Fig. 9, the fuel is admitted at the top and the w'astegases pass downward as indicated by the arrows to supplementary heatingtubes 43 and 44, and thence out by way of flue 45.

According to Fig. 10, the fuel enters at the top and passes down betweenthe bottom boiler tubes to supplementary tubes 46 and 47 and thencethrough an air heater 48 to the flue 49, the heated air being used forcombustion or other desired purpose.

Various other modifications may be made by I those skilled in the art,without departing from the invention as defined in the following claims.

What I claim is:-

1. A boiler having a combustion chamber all the side walls of whichcomprise separate upright steam generating tubes, each wall being closedto prevent the passage of the heating gases between said tubes and eachwall being in line between the outermost tubes of the walls adjacent toit so as to form a complete enclosure with each of the tubes exposed tothe radiant heat of the burning fuel.

2. The boiler of claim 1 in combination with refractory material on theouter sides of the tubes and projections on the tubes embedded in therefractory material and tying it to the tubes.

3. The boiler of claim 1 in combination with headers at the top andbottom respectively of said tubes, the headers at the bottom being indirect communication with each other and those at the top being indirect communication with each rial on the outer sides of the tubes andtied to the tubes.

5. A boiler having a combustion chamber all the side walls of whichcomprise separate upright steam generating tubes, each wall being closedto prevent the passage of the heating gases between said tubes, and eachwall extending continuously between the ends of the walls adjacent to itso as to form a complete closure, in combination with refractorymaterial on the outer sides of the tubes and projections on the tubesembedded in such refractory material and tying it to the tubes.

6. 'I'heboiler of claim 5, and refractory material on the inner sides ofthe tubes covering only the lower portion thereof, leaving the upperportion exposed directly to the heating gases.

THOMAS E. MURRAY.

